In mobile phone and panel display technology, the active matrix organic light emitting diode (AMOLED) panel has gradually become the mainstream of next generation displays due to its advantages such as autonomous luminescence, bright color, low power consumption, and wide visual angle.
The principle of autonomous luminescence of the AMOLED includes: taking the ITO semiconductor electrode and the metal electrode fabricated on the back plate as the anode and the cathode of the device, and evaporating the organic semiconductor material and the light emitting material onto the substrate. Under the driving of the voltage, electrons and holes are injected into the electron and hole transport layers from the cathode and the anode respectively. The electrons and the holes migrate to the light emitting layer through the electron and hole transport layers respectively, and meet in the light emitting layer, so as to form excitons and excite the light emitting molecules. The latter emits visible light through radiative relaxation.
At present, people have more and more requirements on the resolution and the brightness of the mobile phone or the panel. However, there are still many challenges to produce organic light emitting diode (OLED) display screens with a high quality and a high resolution. For an AMOLED with a high resolution, in a conventional pixel array in a strip arrangement as shown in FIG. 1, the three columns of sub-pixels of red, green, and blue (R, G, B) are arranged repeatedly. When performing display, as shown in FIG. 2, the phenomenon of jagged edge is serious. Moreover, because each column only contains sub-pixels of one color, color mixture may also occur easily.